One method of “valuing” documents found in a search is to evaluate the citations made to these documents. For instance, American jurisprudence relies upon precedent. Judges must base their decisions upon principles set out in earlier cases, and must provide precise citations to the earlier decisions upon which they are relying. Consequently, prior art legal search engines have analyzed these citations in order to value documents and to rank search results. The CaseFinder service provided by the assignee of the present invention displays citations to other cases as hyperlinks, where one click takes the user to the text of the cited case. CaseFinder also uses this hyperlinking capability to provide a better search result ranking mechanism. The extent to which a document has been cited by later documents enhances the “value” of that document in search results.
CaseFinder shows the user a list of later cases that cite the found document. CaseFinder can arrange the documents in the list by using two kinds of relevance ranking that rely upon citations. In the first type, CaseFinder ranks documents according to the number of times they had been cited by other documents. The second type of ranking is similar, but in this instance, CaseFinder first assigns a “weight” to a citing document by determining how many times it had been cited. CaseFinder then uses the calculated weight of the citing documents, rather than a simple count of the citing documents, to rank the cited document.